Implantable medical device comprising a wireless transcutaneous link

ABSTRACT

According to an embodiment, a medical device is disclosed. The medical device includes an external unit and an implantable unit. The external unit includes an electronic unit operationally coupled to a transmitter coil that is configured transmit power and/or data signal over a wireless transcutaneous link, a coil unit comprising a loop structure with the transmitter coil being wound around and along at least a part of length of the loop structure, and a fixation unit configured to attach the loop structure to a user&#39;s body i) proximal to an implantable receiver coil that is configured to be implanted within a body part, and ii) around a body part of a user such that a part of the body part is positioned in a hollow section of the loop structure. The implantable unit includes the implantable receiver coil configured to receive the power and/or data signal over the wireless transcutaneous link, a processing unit configured to i) process the received data signal to control functionalities of at least one of the components of the implantable unit, and/or ii) utilize the received power for operation of at least one of the components of the implantable unit. The wireless transcutaneous link includes a coupling between the transmitter coil and the receiver coil, and when the loop structure is attached using the fixation unit, at least a substantial number of magnetic field lines generated in response to excitation of the transmitter coil passes through the implantable receiver coil.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Divisional of U.S. application Ser. No.16/100,875, filed on Aug. 10, 2018, which claims priority under 35U.S.C. § 119(a) to Application No. 17185904.4, filed in Europe on Aug.11, 2017, all of which are hereby expressly incorporated by referenceinto the present application.

FIELD

The present disclosure relates to an implantable medical devicecomprising a transcutaneous link. In particular, the disclosure relatesto an implantable medical device, such as a hearing aid, comprising awireless transcutaneous link for transmitting power and/or data over thelink comprising a coupling between a transmitter coil and an implantablereceiver coil, wherein a coupling coefficient between the transmittercoil and the implantable receiver coil is substantially improved.

BACKGROUND

Any discussion of the prior art throughout the specification in no waybe considered as an admission that such prior art is widely known orforms parts of common general knowledge in the field.

Medical devices having one or more implantable unit, generally referredto as implantable medical devices, have provided a wide range ofbenefits to patients over recent decades. In particular, devices such asimplantable hearing aids, implantable pacemakers, defibrillators, eyeimplant, retina implant, heart pump, drug delivery systems, gastricimplant, nerve stimulators, brain stimulators, functional electricalstimulation devices, such as cochlear prostheses, organ assist orreplacement devices, and other partially or completely-implanted medicaldevices, have been successful in performing life-saving and/or lifestyleenhancement functions for a number of years.

As such, the type of implantable devices and the range of functionsperformed thereby have increased over the years. For example, many suchimplantable medical devices often include one or more instruments,apparatus, sensors, processors, controllers or other functionalmechanical, electrical or electronic components that are permanently ortemporarily implanted in a patient to perform diagnosis, prevention,monitoring, treatment or management of a disease or injury or symptomthereof, or to investigate, replace or modify of the anatomy or of aphysiological process. Many of these implantable components receivepower and/or data over a wireless transcutaneous link from externalunits that are part of, or operate in conjunction with, the implantableunit.

The wireless transcutaneous link is conventionally realized as aninductive link, with an external unit comprising a transmitter coil andan implantable unit comprising a receiver coil. Typically, the receivercoil is implanted, for example in an artificial cavity created in themastoid region or below the skin, and the external unit includes acomponent having a disc-like shape that is attached to the patient'shead in a detachable manner at a position opposite to the implantedreceiver coil such that the two coils are in parallel planes on bothsides (external and implantable positions) of the skin. The externalunit typically includes at least one retention magnet that cooperateswith an implanted retention magnet in order to keep the external unit atthe correct position over the receiver coil such that the transmittercoil is axially aligned to the receiver coil, i.e. coil axis of the twocoils are aligned to each other.

However, such fixation of the external unit via magnetic forces causes arelatively high weight of the external unit and also a relatively largesize of the external unit. This is not only uncomfortable for the userbut also aesthetically unattractive. In addition, the implanted magnethas to be surgically removed or specially designed in case of MRI(Magnetic Resonance Imaging). Moreover, since the attractive forcesbetween the magnets are limited, the external unit may move from thedesired position and even fall down as a result of fast movements of thehead (for example, when the patient jumps).

For a conventional coil arrangement where the transmitter coil and thereceiver coil are either sides of the skin and in parallel planes, thecoupling coefficient is very low because most of the magnetic fieldlines that the transmitter coil generates is not picked up by thereceiver coil, thus leading to poor energy transfer efficiency. Inaddition, as the two coils are located on either side of the skin, anychange in coil separation, for example by way of increase in skinthickness, may result in rapid drop in the coupling coefficient betweenthe two coils. In view of the efficiency problem, the external unitusually includes a relatively huge battery compartment or multiplebatteries so that the implantable medical device is useable for a usageperiod that doesn't cause annoyance for the user, for example requiringthe user to frequently change batteries or recharge the batterycompartment. Besides making the external unit aesthetically lessappealing, the additional weight of the battery compartment or multiplebatteries also require a stronger retention magnet that may possiblylead to discomfort and in extreme cases irritation or infection of theskin that is under constant magnetic attraction force generated betweenthe retention magnet and implantable magnet.

Accordingly, the present disclosure provides an alternative coilarrangement for a wireless transcutaneous link and discloses animplantable medical device that includes a wireless transcutaneous linkwhere one or more of the above-mentioned shortcomings are addressed.

SUMMARY

According to an embodiment, a medical device is disclosed. The medicaldevice includes an external unit and an implantable unit. The externalunit includes an electronic unit operationally coupled to a transmittercoil that is configured transmit power and/or data signal over awireless transcutaneous link, a coil unit comprising a loop structurewith the transmitter coil being wound around and along at least a partof length of the loop structure, and a fixation unit configured toattach the loop structure to a user's body i) proximal to an implantablereceiver coil that is configured to be implanted within a body part, andii) around the body part of a user such that a part of the body part ispositioned in a hollow section of the loop structure. The implantableunit includes the implantable receiver coil configured to receive thepower and/or data signal over the wireless transcutaneous link, aprocessing unit configured to i) process the received data signal tocontrol functionalities of at least one of the components of theimplantable unit, and/or ii) utilize the received power for operation ofat least one of the components of the implantable unit. The wirelesstranscutaneous link includes a coupling between the transmitter coil andthe receiver coil, and when the loop structure is attached using thefixation unit, at least a substantial number of magnetic field linesgenerated in response to excitation of the transmitter coil passesthrough the implantable receiver coil.

The transmitter coil and the implantable coil individually comprises anumber of turns. The number of turns in the transmitter coil and thereceiver coil may be same or different.

In an embodiment, the loop structure is defined by a geometrical shapethat includes a closed curve, defining a closed loop structure, whereina point moving along the closed curve forms a path from a starting pointto a final point that coincides with the starting point when the closedcurve is in a closed mode. In one embodiment, the closed curve mayinclude a single part loop structure comprising an openable section thatincludes a primary end and a secondary end. The openable section isattached to rest section of the loop structure at the primary end and isadapted to open the openable section at the secondary end (i.e. an openmode is defined when the openable section is open) to allow access tothe hollow section and positioning of the part of the body part withinthe hollow section. The closed mode is defined when the openable sectionis engaged with rest of the section at the secondary end to form theclosed curve. Alternatively, the closed curve may include multi-partsloop structure wherein the multi-parts includes a plurality ofdetachable parts, such as a first sub-part and a second sub-part, thatare configured to attach with one another to form a closed loopstructure. The closed mode is defined when the plurality of detachableparts is attached to one another. Accordingly, an open mode may bedefined when the plurality of detachable parts is not attached to oneanother and in the open mode, the loop structure is adapted to allowpositioning of the part of the body part within the hollow section ofthe loop structure. This may be achieved when the loop structure is inthe open mode.

In another embodiment, the loop structure is defined by a geometricalshape that includes an open curve, defining an open loop structure,wherein a point moving along the open curve forms a path from a startingpoint to a final point that is proximal to but separated from thestarting point by a distance. The distance is typically a function of athickness of the body tissue and/or skin to which the loop structure isattached, i.e. the distance is configured such that the loop structureis attachable to the user's body. The distance is selected from a groupconsisting of a length that is smaller than the thickness of the bodytissue, a length that is more than the thickness of the body tissue butis adapted to be reduced such that the changed length is smaller thanthe thickness of the body tissue, and a length that is less (may even beclose to zero) than the thickness of the body tissue but is adapted tobe increased such that the changed length is slightly smaller than thethickness of the body tissue. In these alternatives, it is apparent thatthe length smaller or slightly smaller than the thickness of the bodytissue is adapted in a way such that a compressive retention forcebetween a first end (i.e. first point of the geometrical shape) and asecond end (i.e. second point of the geometrical shape) against the bodytissue is applied. The skilled person would appreciate that the distancemay be changed in order to achieve a balance between reliable retentionand user comfort, especially for extended wearing of the medical device.

In different embodiments, the loop structure may include shape that isselected from a circular, elliptical, rectangular, square, polygonalshape, curved shape or a combination thereof.

The term “proximal” to the receiver coil indicates that the transmittercoil is positioned close to the implantable receiver coil such that aninductive coupling between the transmitter coil and the implantablereceiver coil is achieved. This is achieved when the loop structure isattached to the body part using the fixation unit.

The term “around” a body part indicates that the fixation unit isconfigured to attach the loop structure such that the loop structureextends, with or without piercing the body tissue, between a posteriorside and an anterior side of the body part and with the part of the bodypart being positioned in the hollow section of the loop structure. Theanterior side may be understood as front side relative to the posteriorside, which may be understood as back side. The term “around” a bodypart may also be defined by the fixation unit being configured to attachthe loop structure such that the loop structure extends in a way thatthe first end and the second end of loop structure is adapted tosandwiched a body tissue with the part of the body part being positionedin the hollow section of the loop structure. The term “around” a bodypart may also be defined by the fixation unit being configured to attachthe loop structure such that the loop structure extends in a way thatthe loop structure pierces through the body part with the part of thebody part being positioned in the hollow section of the loop structure.

In one embodiment, the term “hollow section” is defined by an area thatis enclosed by the closed curve when the closed curve is in the closedmode. In another embodiment, the hollow section is defined by an areathat the open curve in combination with an imaginary line joining thedistance separating the first point (first end of the loop structure)and second point (second end of the loop structure) encloses.

The term “positioned” within the hollow section is defined by the partof the body part being received within the area enclosed by the closedcurve or within the area enclosed by the open curve in combination withthe imaginary line.

The term “generated in response to excitation of the transmitter coil”refers to creation of alternating magnetic field on the transmitter coilwhen the transmitter coil is supplied with an electrical current. Thus,the term “excitation” comprises supplying the transmitter coil with anelectrical current. According to the principle of magnetic induction,the alternating magnetic field lines is picked by the implantablereceiver coil and converted into an electrical current in theimplantable receiver coil. The generated electrical current depends onthe coupling between the transmitter and implantable receiver coil, asexpressed by the coupling coefficient. A higher coupling coefficientmeans a more efficient transfer link.

The term “a substantial number of magnetic field lines” passing throughthe implantable receiver coil refers to an electromagnetic couplingbetween the transmitter coil and the implantable efficiency such that acoupling coefficient between the external coil and the implantablereceiver coil is at least 0.5, preferably 0.6, more preferably 0.7, evenmore preferably 0.8 and the most preferably 0.9. It is apparent that inembodiments utilizing closed loop structure, leakage of fieldlines/magnetic flux is minimized and a significantly higher couplingcoefficient of at least 0.7, preferably 0.8 and even more preferably 0.9is achieved. In embodiments utilizing the open loop structure, thesandwiched skin and body tissue may result in some magnetic flux/fieldlines leakage, thus leading to a reduction in coupling coefficient whencompared to the closed loop structure. Nonetheless, even in suchembodiments, a coupling coefficient of at least 0.5, preferably at least0.6 and more preferably 0.7 is achieved. Despite the couplingcoefficient in the open loop structure embodiments being a function ofthickness of the skin and body tissue, the coupling coefficient is stillhigher than the conventional wireless transcutaneous link comprisingparallel transmitter coil-receiver coil set up because the open loopstructure is adapted to guide the magnetic field lines generated inresponse to excitation of the transmitter coil in a focused way towardsthe implantable receiver coil. The term may also refer to “a substantialnumber of magnetic field lines” the magnetic field lines generated inresponse to the excitation of the transmitter coil being primarilyconcentrated within the loop structure and also passing through theimplantable receiver coil. The substantial number of magnetic fieldlines may also be understood as a substantial amount of magnetic flux,which is generated in response to excitation of the transmitter coil.

In different embodiments, the implantable processing unit is animplantable processor and/or an implantable stimulator that isconfigured to generate an output. The output is configured to generateperceivable stimulation for the user. For example, such perceivablestimulation includes perception of sound in case of implantable hearingaids. For the medical device comprising a hearing aid, the output mayinclude a stimulation pulse (usually frequency specific) or signal forgenerating vibrational force (usually frequency specific). In anembodiment, the implantable processing unit comprises a power controlleradapted to control utilization of power received at the implantablereceiver coil.

The term “one of the components of the implantable unit” includes one ormore of processing unit, rechargeable battery, vibrator, vibratory unit,electrode array, pump, sensor, drug capsule and any other implantablecomponent of the medical device.

In different embodiments, the phrase “control functionalities of atleast one of the components of the implantable unit” includes i) theprocessing unit generating, in accordance with the data signal,parameters (like stimulation pulse or signal for generating vibrationalforce) for producing perceivable stimulation like sound perception incochlear implant or in bone conduction hearing aid, and/or ii) electrodearray delivering electrical charges that is dependent upon the generatedparameter (stimulation pulse), and/or iii) vibrator or vibratory unitgenerating vibrations that is dependent upon the generated parameter(signal for generating vibrational force), and/or iv) a sensorcollecting in vivo biological data, and/or v) a pump, such as acontinuous pump or an intermittent pump, pumping bodily fluid such asblood within the body or releasing a drug from an implantablecapsule/container containing the drug, and/or vi) the rechargeablebattery being adapted to be put in charging mode or operational mode.The charging mode is defined when the battery is being charged andoperational mode is defined when the rechargeable battery is adapted toprovide power to the implantable unit components like to the processingunit or electrode array or vibrator or vibratory unit or sensor or pump.The processing unit may also be configured to measure charge level ofthe rechargeable battery and trigger the charging mode when the measuredcharge level is below a minimum threshold level and/or trigger anoperational mode when the measured charge level is above a predeterminedlevel.

The phrase “utilize the received power” includes providing operationalpower to one or more of the processing unit, electrode array, vibrator,vibratory unit, pump, sensor and for recharging of the rechargeablebattery.

In an embodiment, when the loop structure is attached using the fixationunit, at least a substantial number of magnetic field lines generated inresponse to excitation of the transmitter coil encircle the part of thebody part received in the hollow section of the loop structure.

The loop structure is preferably a solid loop that is made up of amagnetic, like ferrite, material preferably having a high magneticpermeability. Such high magnetic permeability is at least 10, preferablyat least 100, more preferably at least 1000. Such material may beselected from a group consisting of a ferrite materials, and soft iron.Other commercially available products under brand names VACOFLUX™,VACODUR™, VOCADUR S PLUS™, TRAFOPERM™, CRYOPERM™, PERMAX™, PERMENORM™,ULTRAPERM™, VACOPERM™, CHRONOPERM™, MEGAPERM™, MUMETALL™, RECOVAC™, andTHERMOFLUX™, as produced by Vacuumschmelze GmbH & Co. KG or REMKO™ asproduced by Uddeholm A/S may also be used. As the loop structure is madeup of a magnetic material, most of the field lines are concentratedwithin the magnetic material and thus allow for a high couplingcoefficient between the primary coil and the secondary coil. It would beapparent to the skilled person that a material of different magneticpermeability may also be used so long as the material has high enoughmagnetic permeability to guide the field lines generated in response toexcitation of the transmitter coil in a focused way towards theimplantable receiver coil in a way explained in this disclosure.

In several embodiments, the loop structure comprises the fixation unit.In other words, the fixation unit is part of the loop structure and maydefine a part of the loop axis.

In an embodiment, the fixation unit is adapted to attach the loopstructure with respect to the implantable receiver coil in anarrangement such that one section of the implantable receiver coil ispositioned within the hollow section of the loop structure whereas theother section of the implantable receiver coil is positioned outside thehollow section of the loop structure.

In an embodiment, the lengthwise distance between the transmitter coiland receiver coil is more than diameter of the receiver coil.Additionally, or alternatively, the lengthwise distance between thetransmitter coil and receiver coil is more than diameter of thetransmitter coil. In these embodiments, the lengthwise distance includesthe shortest distance from at least one of the ends of the transmittercoil on the loop structure along length of the loop structure to planarsurface of the implantable receiver coil.

In an embodiment, the medical device does not include an implantableretention magnet for attaching the external unit. Thus, the fixationunit is adapted to prevent utilizing an implantable retention magnet toattach the loop structure to the user's body. This is particularlyuseful for MRI as the need to remove an implantable magnet or speciallydesign an implantable retention magnet is obviated.

In an embodiment, at least one turn of the transmitter coil isnon-parallel to the implantable receiver coil. Additionally, oralternatively, at least one turn of the transmitter coil is non-coaxialwith the receiver coil.

In an embodiment, the transmitter coil and the implantable receiver coilare adapted to be arranged relative to each other such that the couplingcoefficient between the transmitter coil and the implantable receivercoil is independent of orientation of the transmitter coil with respectto the implantable receiver coil. The orientation refers to the co-axialand/or planar alignment of the transmitter coil with respect to theimplantable receiver coil.

In an embodiment, the fixation unit is configured to attach the loopstructure proximal to the implantable receiver coil such that a loopaxis or an extrapolated loop axis of the loop structure passes throughthe implantable receiver coil. In one embodiment disclosing a loopstructure defined by the closed curve geometrical shape, the loop axisis defined as an axis that runs along the entire length of the loopstructure. In another embodiment disclosing a loop structure defined bythe open curve geometrical shape, the extrapolated loop axis is definedby an axis that runs along the entire length of the loop structure andan imaginary line joining the distance separating the first point (firstend of the loop structure) and second point (second end of the loopstructure).

The medical device according to any of the preceding claims, wherein thefixation unit is configured to attach the loop structure around the bodypart such that the loop structure and the implantable receiver coil arearranged in an interlocked hopf link configuration. As most (substantialnumber) of the field lines are concentrated within the loop structure,an interlocked hopf link configuration between the loop structure andthe implantable receiver coil allows for obtaining a high couplingcoefficient between the transmitter coil (wound around the loopstructure) and the implantable receiver coil. In one embodimentdisclosing a loop structure defined by the closed curve geometricalshape, the hopf link defines a loop structure that is mechanicallylocked together with the implantable receiver coil in a hopfconfiguration. In another embodiment disclosing a loop structure definedby the open curve geometrical shape, the hopf link defines a loopstructure that is locked together with the implantable receiver coil bythe imaginary line of the extrapolated loop axis. In these embodiments,i) one of the loop structure (closed loop structure) or imaginary lineof the extrapolated loop axis (open loop structure) is adapted to passthrough center of the implantable receiver coil, and/or ii) theimplantable receiver coil is adapted to pass through center of the loopstructure. Alternatively, i) one of the loop structure (closed loopstructure) or imaginary line of the extrapolated loop axis (open loopstructure) is adapted to prevent passing through center of theimplantable receiver coil, and/or ii) the implantable receiver coil isadapted to prevent passing through center of the loop structure.

In an embodiment, the fixation unit is configured to attach the loopstructure around the body part such that i) the loop structure and theimplantable receiver coil are arranged in an interlocked first hopf linkconfiguration, and ii) the loop structure and the transmitter coil arearranged in an interlocked second hopf link configuration. In thisembodiment, the first hopf link configuration includes any or all thefeatures disclosed for interlocked hopf link configuration from thepreceding paragraph. Because of the first hopf link configuration andsecond hopf link configuration, a substantial number of magnetic fieldlines are concentrated within the loop structure and passes through thereceiver coil, thereby substantially improving the coupling coefficient.

In an embodiment, the implantable receiver coil is in a first plane andthe loop structure is along a second plane, the first plane and thesecond plane being at least substantially perpendicular to each other.

In an embodiment, the loop structure includes an openable closed loopstructure comprising a section that is configured to penetrate throughthe body part at least at one point of the body part. As describedearlier, the closed loop structure may be defined by the closed curve.In an embodiment, the openable closed loop structure includes a closedloop structure comprising an openable section that includes a primaryend and a secondary end. The openable section is attached to restsection of the loop structure at the primary end and adapted to open thesection at the secondary end (i.e. defining an open mode when thesection is opened) to allow access to the hollow section and positioningof the part of the body part within the hollow section. The closed modeis defined when the openable section is engaged with rest of the sectionat the secondary end to form the closed curve. The openable section isadapted (typically through use of the fixation unit) to penetratethrough the body part at least at one point of the body part. Inparticular, the secondary end of the openable section is adapted topenetrate through the body part at least at one point of the body part.Alternatively, the openable closed loop structure may includemulti-parts loop structure wherein the multi-parts includes a pluralityof detachable parts that are configured to attach with one another toform a closed loop structure. The closed mode is defined when theplurality of detachable parts is attached to one another. Accordingly,an open mode may be defined when the plurality of detachable parts isnot attached to one another and in the open mode, the loop structure isadapted to allow positioning of a part of the body part within thehollow section of the loop structure. The plurality of detachable partsindividually includes at least a first end and a second end. The firstends of the plurality of detachable parts and the second ends of theplurality of detachable parts are adapted to connected to each otherrespectively to form a closed loop structure. At least one of the firstends or the second ends of at least one of the plurality of detachableparts is adapted to penetrate through the body part at least at onepoint of the body part.

In any of the embodiments for the openable closed loop structure, theopenable closed loop structure is adapted to penetrate through the bodypart at least at one point of the body part. Such at least one pointincludes at least one hole that is provided at the body part and theimplantable coil is adapted to be implanted and arranged around one ormore holes of the at least one hole. The term “around” refers to theimplantable receiver coil being adapted to encircle the one or moreholes of the at least one hole.

In another embodiment, the loop structure comprises an openable openloop structure comprising a slit having a first slit end configured toabut a first skin surface of the user and a second slit end, opposite tothe first slit end, configured to abut a second skin surface of theuser, the first skin surface and the second skin surface being separatedby a body tissue. As described earlier, the open loop structure may bedefined by the open curve. The first slit end and the second slit endare generally separated by a distance, which is typically a function ofthickness of the body tissue to which the loop structure is attached.

The distance is selected from a group consisting of i) a length that issmaller than the thickness of the body tissue, ii) a length that is morethan the thickness of the body tissue but is adapted to be reduced suchthat the changed length is smaller than the thickness of the bodytissue, and iii) a length that is less (may even be close to zero) thanthe thickness of the body tissue but is adapted to be increased suchthat the changed length is slightly smaller than the thickness of thebody tissue. The openable open loop structure includes means (typicallypart of the fixation unit) adapted to change the distance in order toallow positioning the part of the body part within the hollow section ofthe loop structure. For example, the means is adapted to increase thedistance in the situations i) or iii) and to reduce the distance insituation ii).

In any of the embodiments for the openable open loop structure, thelength smaller or slightly smaller than the thickness of the body tissueis adapted in a way such that a compressive retention force between afirst slit end and second slit end against the body tissue is applied.The distance may be further adapted in order to achieve a balancebetween reliable retention and user comfort, especially for extendedwearing of the medical device. In an embodiment, the first slit end andthe second slit end are configured to abut the first skin surface at afirst point and the second skin surface at a second point, opposite tothe first point, and the implantable coil is adapted to be implanted andarranged around the first point and the second point. The term “around”refers to the implantable receiver coil being adapted to encircle thebody tissue sandwiched between the first end (point) and the second end(point). The body tissue encircle by the receiver coil is typicallyincludes the tissue part that is passed through by the imaginary line ofthe extrapolated loop axis.

The first slit end is adapted to face a first planar side of theimplantable receiver coil; and a second slit end is adapted to face asecond planar side, opposite to the first planar side, of theimplantable receiver coil. Thus, the first slit end is adapted to abutthe first skin surface at the first point and the second slit end isadapted to abut the second skin surface at the second point.

In an embodiment, diametric dimensions of the implantable receiver coilis at least same as width of the loop structure. The width refers tocross-sectional thickness of the loop structure. In another embodiment,planar area of the implantable receiver coil is at least same as thecross sectional area of the loop structure at an interface of the loopstructure. The cross sectional area of the loop structure at theinterface of the loop structure may include i) cross sectional area atthe first end and or the second end of the loop structure, or ii) crosssectional area of the section of the loop structure that penetratesthrough the body part at least at one point of the body part.

In an embodiment, the implantable unit comprises an implantable magneticcore that is configured to be positioned within an area enclosed by aperimeter of the implantable receiver coil. The magnetic core allows foran increased number of magnetic field lines being picked up the receivercoil, thereby further increases the coupling coefficient between thetransmitter coil and the implantable receiver coil.

In an embodiment, a substantial number of magnetic field lines generatedin response to excitation of the transmitter coil are generated withinthe loop structure. As the loop structure is made of a magneticmaterial, the field lines are concentrated within and along the lengthof the loop structure. In the closed loop structure, such length wouldinclude the entire length of the loop structure. In the open loopstructure, such length would include the entire length of the loopstructure in combination with length of the imaginary line that connectstwo ends of the loop structure, the two ends being configured to bepositioned on either side of the body part. It is understandable thatthe imaginary line in physical context would be contained by skin andbody tissue that is sandwiched between the two ends. Although thesandwiched skin and body tissue may result in a reduction in couplingcoefficient because of leakage when compared to using the closed loopstructure. Nonetheless, the skilled person would appreciate that despitesome leakage, a substantial amount of magnetic field lines generated inresponse to excitation of the transmitter coil would still follow thepath of the imaginary line because of the short distance between firstend and the second end of the loop structure, in particular, when theimplantable magnetic core is configured to be positioned within the areaenclosed by the perimeter of the implantable receiver coil.

In an embodiment, at least one turn of the transmitter coil isnon-parallel to the implantable receiver coil. As the transmitter coilis wound around the loop structure, the alignment coaxial and/orparallel alignment of the transmitter coil with respect to theimplantable receiver coil is not critical in order to achieve highcoupling coefficient. Thus, the transmitter coil and the implantablereceiver coil are arranged relative to each other such that the couplingcoefficient between the transmitter coil and the implantable receivercoil is independent of orientation of the transmitter coil with respectto the implantable receiver coil. This is made possible because thecoupling is dependent upon the positioning of the loop structure inrelation to the implantable receiver coil. The “orientation” refers tothe co-axial and/or planar alignment of the transmitter coil withrespect to the implantable receiver coil.

In an embodiment, the loop structure comprises a first sub-structure anda second sub-structure, the first sub-structure and second sub-structurebeing configured to operationally connect with each other to form theopenable closed loop structure or openable open loop structure. In anembodiment, the first sub-structure and the second sub-structureindividually includes at least a first end and a second end. The firstends of the first sub-structure and the second sub-structure and thesecond ends of the first sub-structure and the second sub-structure areadapted to connect to each other respectively to form the openableclosed loop structure. Alternatively, the one of the first ends of thefirst sub-structure and the second sub-structure or the second ends ofthe first sub-structure and the second sub-structure are adapted toconnect to each other respectively to form the openable open loopstructure with a distance between one of the first end-second end pair.

In an embodiment, the fixation unit is selected from a group consistingof a non-magnetic fixation unit and a fixation mechanism that is adaptedto attach the loop structure to a user's body independent of anycooperation (interaction) with the implantable unit. Such cooperationovercomes the requirement of conventionally known systems where theimplantable retention magnet cooperates with an external retentionmagnet for attaching the external unit to the user's body.

In an embodiment, the fixation unit is selected from a group consistingof a clamp mechanism, spring mechanism, piercing pin mechanism,snap-coupling mechanism between the first sub-structure and secondsub-structure, a magnetic coupling mechanism between the firstsub-structure and second sub-structure, and a combination thereof.

In an embodiment, the body part includes an earlobe such that thereceiver coil is configured to be implanted within the earlobe of theuser; and the fixation unit is configured to attach the loop structurearound the earlobe such that the loop structure extends, with (such asin the closed loop structure) or without (such as in open loopstructure) piercing through the earlobe, between a posterior side and ananterior side of the earlobe and with a part of the ear lobe beingpositioned in the hollow section of the loop structure. A section of theimplantable coil is received in the hollow section of the loop structurewhereas rest section of the implantable coil is outside the hollowsection of the loop structure.

In an embodiment, the body part includes periumbilical region of theuser such that the receiver coil is configured to be implanted withinthe periumbilical region preferably around an umbilicus of the user; andthe fixation unit is configured to attach the loop structure around askin in the periumbilical region such that the loop structure extends,with (such as in the closed loop structure) or without (such as in openloop structure) piercing through the skin, between a posterior side andan anterior side of the skin and with a part of the skin beingpositioned in the hollow section of the loop structure. A section of theimplantable coil is received in the hollow section of the loop structurewhereas rest section of the implantable coil is outside the hollowsection of the loop structure.

In different embodiments, the body part may include other implantationsites on the user's body such as tragus, body tissue over mastoidregion, superciliary arch, and any other suitable location.

In embodiments utilizing the closed loop structure, the fixation unit isadapted to penetrate through the body part at least at one point of thebody part. The body part is selected such that the skin at the body partis adapted i) to allow penetration of the fixation unit through anopening/hole at the at least one point, and ii) to grow at periphery ofthe through opening/hole and sealing off the body tissue around the atleast one point against ingress of material like dirt, sweat, etc. Suchgrowth of skin at the periphery may occur over a period of healing time.The growth at the periphery and sealing of the body tissue may becomparable to healing of an earhole (puncture in the earlobe) after asuccessful cosmetic earlobe piercing.

In an embodiment, the processing unit is configured to process thereceived data signal and generate an output. The output is configured togenerate perceivable stimulation for the user. For example, suchperceivable stimulation includes perception of sound in case ofimplantable hearing aids. The medical device thus may be selected from agroup consisting of one or more of

i) an implantable hearing aid comprising a cochlear implant comprisingan implantable electrode array configured to be positioned within acochlea of the user, the electrode array being configured to deliverelectrical charges in accordance with the output,

ii) an implantable hearing aid comprising an auditory transmodiolarimplant comprising an implantable electrode array configured to bepositioned within a modiolus of the user, the electrode array beingconfigured to deliver electrical charges in accordance with the output,

iii) an implantable hearing aid comprising an auditory brainstem implantcomprising an implantable electrode array (typically provided as a pad)configured to be implanted directly onto brainstem, the electrode arraybeing configured to deliver the electrical charges in accordance withthe output,

iv) an implantable hearing aid comprising a bone conduction hearing aidcomprising an implantable vibrator configured to be attached to skull ofthe user, the vibrator being configured to generate vibrations inaccordance with the output,

v) an implantable hearing aid comprising a middle ear implant comprisinga vibratory unit configured to attach to one of the bones of the middleear and/or to one of the windows of the cochlea, the vibratory unitbeing configured to generate vibrations in accordance with the output,

vi) an artificial pacemaker comprising an electrode array configured todeliver electrical charges in accordance with the output,

vii) an implantable heart pump such as a ventricular assist device (VAD)comprising a pump configured to be attached to a user's heart, the pumpbeing configured to provide blood flow within user's body, and

vii) an implantable drug delivery system comprising an implantablecapsule comprising a drug and a pump that is configured to attach to theimplantable capsule and release, through a pumping action, a predefinedamount of drug from the capsule to the user's body. In this embodiment,the drug delivery system may further include an implantable sensor thatis configured to capture a biological data such as blood glucose level.The implantable processing unit is configured to receive the biologicaldata and compare the received data with a stored normal range todetermine a difference and accordingly, based on the difference,determine the amount of drug (predefined amount) to be released. Thenormal range, along with difference to amount of releasable drug may bestored as a look up table in a memory that the processing unit isconfigured to access. The processing unit is further configured, basedon the determined predefined amount, to activate the pump (adapted tooperationally connect to the capsule) for a duration that lets thepredefined amount of the drug to be released from the capsule,

viii) implantable deep brain stimulators or implantable nervestimulators comprising an implantable electrode array configured to beimplanted directly or indirectly onto the brain or nerve respectively,the electrode array being configured to deliver the electrical chargesin accordance with the output comprising a stimulation pulse. Thedelivered electrical charges may be utilized to provide brain withinformation,

viii) eye implants or retina implants comprising a camera for capturingimages and an implantable electrode array configured to deliverelectrical charges in accordance with the captured images,

ix) an implantable cardioverter defibrillator comprising an electrodearray (usually as electrical pads) configured to deliver electricalcharges (for example by way of electrical shock) in accordance with acomparison of monitored rate and rhythm of the heart with a presetnumber. In this embodiment, the defibrillator may also include sensorsin order to monitor the rate and rhythm of the heart,

x) an implantable gastric stimulator configured to be implanted in anabdomen of the user and comprising an electrode array that is configuredto deliver electrical charges (typically by way of mild electricalpulses) to nerves and smooth muscle of lower stomach of the user, and

xi) an implantable brain computer interface system comprising animplantable sensor adapted to capture neural signals in response tobrain activity. The system may further include an implantabletransmitter coil adapted to transmit the neural signals as data packetover the wireless transcutaneous link to an external receiver coil. Theimplantable transmitter coil and external receiver coil is describedlater in embodiments relating to telemetry feedback data.

In the above paragraph, one or more of refers to use of a medical deviceor a combination thereof. For example, a cochlear implant may be usedalone but may also be used in combination such as providing mechanicalstimulation by way of bone conduction hearing aid at a first ear and anelectrical stimulation by way of cochlear implant at a second ear of theuser. In another example, the same user may be utilizing a cochlearimplant as well as an implantable cardioverter defibrillator. Other suchexamples of combinations are within the scope of this disclosure. If theuser is implanted with more than one medical device, a singletransmitter coil-receiver coil pair may be used for providing dataand/or power to the more than one implantable medical devices. Inanother embodiment, each of the implantable medical device may beprovided with a dedicated transmitter coil-receiver coil pair. In eitherembodiment, the transmitter coil-receiver coil pair refers to thewireless transcutaneous link that is in accordance with this disclosure.

In embodiments where the medical device includes the implantable hearingaid, the external unit typically includes a microphone array adapted tocapture sound from user's environment. The microphone array isconfigured to generate an electrical signal. The microphone array may beconfigured to provide direction-dependent signal processing in differentbeamforming modes. Beamforming involves processing sound received at themicrophones of the array in such a way as to make the array act as ahighly directional microphone. Additionally, the external unit mayfurther include a filter bank, configured to receive the electricalsignal, includes an array of frequency specific signal filters thatseparates the incoming electrical signal, such as speech or music, intothe plurality of band pass limited electrical signals. Typically, thefilter bank has a number of narrow frequency band filters with eachfilter associated with a specific band of audio frequencies. Theincoming audio signal is thus filtered into the plurality of band passlimited electrical signals where each signal corresponds to the band offrequencies for one of the band pass filters.

The external unit includes the electronic unit comprising a processorconfigured to process the electrical signal or band pass limitedelectrical signals to compensate for hearing loss of the user, thusgenerating a processed electrical signal. The processor is furtheradapted to encode the processed electrical signal and transmit theprocessed electrical signal in form of the data signal over the wirelesstranscutaneous link from the transmitter coil to the implantablereceiver coil. To achieve this, the external unit comprises a powersource and the processor is configured to draw required current form thepower source to excite (supply electrical current) the transmitter coilfor generating magnetic lines required for transmission of the datasignal. The implanted receiver coil is adapted to receive the datasignal. The implantable processing unit is configured to decode the datasignal and accordingly generate the output such as a stimulation pulse(usually frequency specific) or a signal for generating vibrationalforce (usually frequency specific). Depending upon the hearing aid type,the output is delivered to an implantable electrode or implantablevibrator or implantable vibratory unit in order to produce an electricalstimulation by way of delivery of electrical charges or generatingvibrations. Additionally, the external processor may be configured todraw sufficient current from the power source for exciting thetransmitter coil such that both data signal and power may be transmittedover the wireless transcutaneous link from the transmitter coil to thereceiver coil. The processing unit is configured to utilize the powerreceived at the implantable receiver coil for operation of at least oneof the components of the implantable unit. The implantable unit mayinclude an energy storage unit such as capacitors or rechargeablebattery that is adapted to store the received power. The stored receivedpower is utilized for the operation of one at least one of thecomponents of the implantable unit.

In embodiments where the medical device includes the implantable hearingaid, the implantable unit may include a rechargeable battery. Theexternal unit includes a power source that is adapted to excite thetransmitter coil and transfer only power over the wirelesstranscutaneous link from the transmitter coil to the implantablereceiver coil. The receiver coil is adapted to receive the power and thereceived power is used to charge the rechargeable battery, which isadapted to provide operational power at least one of the components ofimplantable unit including the processing unit. The implantable unit mayfurther include, as disclosed earlier, a microphone array that isadapted to generate the electrical signal may apply beamformingtechniques with our without filtering using the filterbank. Theimplantable processing unit is adapted to utilize the power receivedfrom the rechargeable battery and process the electrical signal tocompensate for hearing loss of the user, thus generating a processedelectrical signal (output). Depending upon the hearing aid type, theoutput is delivered to an implantable electrode or implantable vibratoror implantable vibratory unit in order to produce an electricalstimulation by way of delivery of electrical charges or generatevibrations.

According to another embodiment, a medical device is disclosed. Themedical device includes an external unit and an implantable unit. Theexternal unit includes an electronic unit operationally coupled to atransmitter coil that is configured transmit power and/or data signalover a wireless transcutaneous link, a coil unit comprising a loopstructure with the transmitter coil being wound around and along atleast a part of length of the loop structure, a fixation unit configuredto attach the loop structure to a user's body i) proximal to animplantable receiver coil that is configured to be implanted within abody part, and ii) around the body part of a user such that a part ofthe body part is positioned in a hollow section of the loop structure.The implantable unit includes the implantable receiver coil configuredto receive the power and/or data signal over the wireless transcutaneouslink, a processing unit configured to i) process the received datasignal to control functionalities of at least one of the components ofthe implantable unit, and/or ii) utilize the received power foroperation of at least one of the components of the implantable unit. Thewireless transcutaneous link includes a coupling between the transmittercoil and the receiver coil, and the fixation unit is adapted to attachthe loop structure with respect to the implantable receiver coil in anarrangement such that one section of the implantable receiver coil ispositioned within the hollow section of the loop structure whereas theother section of the implantable receiver coil is positioned outside thehollow section of the loop structure.

According to another embodiment, a medical device is disclosed. Themedical device includes an external unit and an implantable unit. Theexternal unit includes an electronic unit operationally coupled to atransmitter coil that is configured transmit power and/or data signalover a wireless transcutaneous link, a coil unit comprising a loopstructure with the transmitter coil being wound around and along atleast a part of length of the loop structure, a fixation unit configuredto attach the loop structure to a user's body i) proximal to animplantable receiver coil that is configured to be implanted within abody part, and ii) around the body part of a user such that a part ofthe body part is positioned in a hollow section of the loop structure.The implantable unit includes the implantable receiver coil configuredto receive the power and/or data signal over the wireless transcutaneouslink, a processing unit configured to i) process the received datasignal to control functionalities of at least one of the components ofthe implantable unit, and/or ii) utilize the received power foroperation of at least one of the components of the implantable unit. Thewireless transcutaneous link includes a coupling between the transmittercoil and the receiver coil, and the fixation unit is configured toattach the loop structure proximal to the implantable receiver coil suchthat a loop axis or an extrapolated loop axis of the loop structurepasses through the implantable receiver coil.

According to another embodiment, a medical device is disclosed. Themedical device includes an external unit and an implantable unit. Theexternal unit includes an electronic unit operationally coupled to atransmitter coil that is configured transmit power and/or data signalover a wireless transcutaneous link, a coil unit comprising a loopstructure with the transmitter coil being wound around and along atleast a part of length of the loop structure, a fixation unit configuredto attach the loop structure to a user's body i) proximal to animplantable receiver coil that is configured to be implanted within abody part, and ii) around the body part of a user such that a part ofthe body part is positioned in a hollow section of the loop structure.The implantable unit includes the implantable receiver coil configuredto receive the power and/or data signal over the wireless transcutaneouslink, a processing unit configured to i) process the received datasignal to control functionalities of at least one of the components ofthe implantable unit, and/or ii) utilize the received power foroperation of at least one of the components of the implantable unit. Thewireless transcutaneous link includes a coupling between the transmittercoil and the receiver coil, and the fixation unit is configured toattach the loop structure around the body part such that the loopstructure and the implantable receiver coil are arranged in aninterlocked hopf link configuration.

According to another embodiment, a medical device is disclosed. Themedical device includes an external unit and an implantable unit. Theexternal unit includes an electronic unit operationally coupled to atransmitter coil that is configured transmit power and/or data signalover a wireless transcutaneous link, a coil unit comprising a loopstructure with the transmitter coil being wound around and along atleast a part of length of the loop structure, a fixation unit configuredto attach the loop structure to a user's body i) proximal to animplantable receiver coil that is configured to be implanted within abody part, and ii) around the body part of a user such that a part ofthe body part is positioned in a hollow section of the loop structure.The implantable unit includes the implantable receiver coil configuredto receive the power and/or data signal over the wireless transcutaneouslink, a processing unit configured to i) process the received datasignal to control functionalities of at least one of the components ofthe implantable unit, and/or ii) utilize the received power foroperation of at least one of the components of the implantable unit. Thewireless transcutaneous link includes a coupling between the transmittercoil and the receiver coil. The fixation unit is configured to attachthe loop structure around the body part such that i) the loop structureand the implantable receiver coil are arranged in an interlocked firsthopf link configuration, and ii) the loop structure and the transmittercoil are arranged in an interlocked second hopf link configuration.

According to another embodiment, a medical device is disclosed. Themedical device includes an external unit and an implantable unit. Theexternal unit includes an electronic unit operationally coupled to atransmitter coil that is configured transmit power and/or data signalover a wireless transcutaneous link, a coil unit comprising a loopstructure with the transmitter coil being wound around and along atleast a part of length of the loop structure, a fixation unit configuredto attach the loop structure to a user's body i) proximal to animplantable receiver coil that is configured to be implanted within abody part in a first plane, and ii) around the body part of a user suchthat a part of the body part is positioned in a hollow section of theloop structure. The implantable unit includes the implantable receivercoil configured to receive the power and/or data signal over thewireless transcutaneous link, a processing unit configured to i) processthe received data signal to control functionalities of at least one ofthe components of the implantable unit, and/or ii) utilize the receivedpower for operation of at least one of the components of the implantableunit. The wireless transcutaneous link includes a coupling between thetransmitter coil and the receiver coil. When the loop structure isattached using the fixation unit, the loop structure is arranged in asecond plane such that the first plane and the second plane are at leastsubstantially perpendicular to each other.

According to another embodiment, a medical device is disclosed. Themedical device includes an external unit and an implantable unit. Theexternal unit includes an electronic unit operationally coupled to atransmitter coil that is configured transmit power and/or data signalover a wireless transcutaneous link, a coil unit comprising a loopstructure with the transmitter coil being wound around and along atleast a part of length of the loop structure, a fixation unit configuredto attach the loop structure to a user's body i) proximal to animplantable receiver coil that is configured to be implanted within abody part, and ii) around the body part of a user such that a part ofthe body part is positioned in a hollow section of the loop structure.The implantable unit includes the implantable receiver coil configuredto receive the power and/or data signal over the wireless transcutaneouslink, a processing unit configured to i) process the received datasignal to control functionalities of at least one of the components ofthe implantable unit, and/or ii) utilize the received power foroperation of at least one of the components of the implantable unit. Thewireless transcutaneous link includes a coupling between the transmittercoil and the receiver coil, and the loop structure comprises an openableclosed loop structure comprising a section that is configured topenetrate through the body part at least at one point of the body part.

According to another embodiment, a medical device is disclosed. Themedical device includes an external unit and an implantable unit. Theexternal unit includes an electronic unit operationally coupled to atransmitter coil that is configured transmit power and/or data signalover a wireless transcutaneous link, a coil unit comprising a loopstructure with the transmitter coil being wound around and along atleast a part of length of the loop structure, a fixation unit configuredto attach the loop structure to a user's body i) proximal to animplantable receiver coil that is configured to be implanted within abody part, and ii) around the body part of a user such that a part ofthe body part is positioned in a hollow section of the loop structure.The implantable unit includes the implantable receiver coil configuredto receive the power and/or data signal over the wireless transcutaneouslink, a processing unit configured to i) process the received datasignal to control functionalities of at least one of the components ofthe implantable unit, and/or ii) utilize the received power foroperation of at least one of the components of the implantable unit. Thewireless transcutaneous link includes a coupling between the transmittercoil and the receiver coil. The loop structure comprises an openableopen loop structure comprising a slit having a first end configured toabut a first skin surface of the user and a second end, opposite to thefirst end, configured to abut a second skin surface of the user, thefirst skin surface and the second skin surface being separated by a bodytissue.

According to another embodiment, a medical device is disclosed. Themedical device includes an external unit and an implantable unit. Theexternal unit includes an electronic unit operationally coupled to atransmitter coil that is configured transmit power and/or data signalover a wireless transcutaneous link, a coil unit comprising a loopstructure with the transmitter coil being wound around and along atleast a part of length of the loop structure, a fixation unit configuredto attach the loop structure to a user's body i) proximal to animplantable receiver coil that is configured to be implanted within abody part, and ii) around the body part of a user such that a part ofthe body part is positioned in a hollow section of the loop structure.The implantable unit includes the implantable receiver coil configuredto receive the power and/or data signal over the wireless transcutaneouslink, a processing unit configured to i) process the received datasignal to control functionalities of at least one of the components ofthe implantable unit, and/or ii) utilize the received power foroperation of at least one of the components of the implantable unit. Thewireless transcutaneous link includes a coupling between the transmittercoil and the receiver coil, and diametric dimensions of the implantablereceiver coil are at least same as width of the loop structure.

According to another embodiment, a medical device is disclosed. Themedical device includes an external unit and an implantable unit. Theexternal unit includes an electronic unit operationally coupled to atransmitter coil that is configured transmit power and/or data signalover a wireless transcutaneous link, a coil unit comprising a loopstructure with the transmitter coil being wound around and along atleast a part of length of the loop structure, a fixation unit configuredto attach the loop structure to a user's body i) proximal to animplantable receiver coil that is configured to be implanted within abody part, and ii) around the body part of a user such that a part ofthe body part is positioned in a hollow section of the loop structure.The implantable unit includes the implantable receiver coil configuredto receive the power and/or data signal over the wireless transcutaneouslink, a processing unit configured to i) process the received datasignal to control functionalities of at least one of the components ofthe implantable unit, and/or ii) utilize the received power foroperation of at least one of the components of the implantable unit. Thewireless transcutaneous link includes a coupling between the transmittercoil and the receiver coil, and at least one turn of the transmittercoil is non-parallel to the implantable receiver coil.

According to another embodiment, a medical device is disclosed. Themedical device includes an external unit and an implantable unit. Theexternal unit includes an electronic unit operationally coupled to atransmitter coil that is configured transmit power and/or data signalover a wireless transcutaneous link, a coil unit comprising a loopstructure with the transmitter coil being wound around and along atleast a part of length of the loop structure, a fixation unit configuredto attach the loop structure to a user's body i) proximal to animplantable receiver coil that is configured to be implanted within abody part, and ii) around a body part of a user such that a part of thebody part is positioned in a hollow section of the loop structure. Theimplantable unit includes the implantable receiver coil configured toreceive the power and/or data signal over the wireless transcutaneouslink, a processing unit configured to i) process the received datasignal to control functionalities of at least one of the components ofthe implantable unit, and/or ii) utilize the received power foroperation of at least one of the components of the implantable unit. Thewireless transcutaneous link includes a coupling between the transmittercoil and the receiver coil. The loop structure comprises a firstsub-structure and a second sub-structure, the first sub-structure and asecond sub-structure being configured to operationally connect with eachother to form the openable closed loop structure or openable open loopstructure.

According to another embodiment, a medical device is disclosed. Themedical device includes an external unit and an implantable unit. Theexternal unit includes an electronic unit operationally coupled to atransmitter coil that is configured transmit power and/or data signalover a wireless transcutaneous link, a coil unit comprising a loopstructure with the transmitter coil being wound around and along atleast a part of length of the loop structure, a fixation unit configuredto attach the loop structure to a user's body i) proximal to animplantable receiver coil that is configured to be implanted within abody part, and ii) around a body part of a user such that a part of thebody part is positioned in a hollow section of the loop structure. Theimplantable unit includes the implantable receiver coil configured toreceive the power and/or data signal over the wireless transcutaneouslink, a processing unit configured to i) process the received datasignal to control functionalities of at least one of the components ofthe implantable unit, and/or ii) utilize the received power foroperation of at least one of the components of the implantable unit. Thewireless transcutaneous link includes a coupling between the transmittercoil and the receiver coil, and a lengthwise distance between thetransmitter coil and implantable receiver coil is more than at least oneof diameter of the transmitter coil or diameter of the implantablereceiver coil.

According to another embodiment, a medical device is disclosed. Themedical device includes an external unit and an implantable unit. Theexternal unit includes an electronic unit operationally coupled to atransmitter coil that is configured transmit power and/or data signalover a wireless transcutaneous link, a coil unit comprising a loopstructure with the transmitter coil being wound around and along atleast a part of length of the loop structure, a fixation unit configuredto attach the loop structure to a user's body i) proximal to animplantable receiver coil that is configured to be implanted within abody part, and ii) around a body part of a user such that a part of thebody part is positioned in a hollow section of the loop structure. Theimplantable unit includes the implantable receiver coil configured toreceive the power and/or data signal over the wireless transcutaneouslink, a processing unit configured to i) process the received datasignal to control functionalities of at least one of the components ofthe implantable unit, and/or ii) utilize the received power foroperation of at least one of the components of the implantable unit. Thewireless transcutaneous link includes a coupling between the transmittercoil and the receiver coil, and the transmitter coil and the implantablereceiver coil are arranged relative to each other such that the couplingcoefficient between the transmitter coil and the implantable receivercoil is independent of orientation of the transmitter coil with respectto the implantable receiver coil.

According to another embodiment, a medical device is disclosed. Themedical device includes an external unit and an implantable unit. Theexternal unit includes an electronic unit operationally coupled to atransmitter coil that is configured transmit power and/or data signalover a wireless transcutaneous link, a coil unit comprising a loopstructure with the transmitter coil being wound around and along atleast a part of length of the loop structure, a fixation unit configuredto attach the loop structure to a user's body i) proximal to animplantable receiver coil that is configured to be implanted within abody part, and ii) around a body part of a user such that a part of thebody part is positioned in a hollow section of the loop structure. Theimplantable unit includes the implantable receiver coil configured toreceive the power and/or data signal over the wireless transcutaneouslink, a processing unit configured to i) process the received datasignal to control functionalities of at least one of the components ofthe implantable unit, and/or ii) utilize the received power foroperation of at least one of the components of the implantable unit. Thewireless transcutaneous link includes a coupling between the transmittercoil and the receiver coil, and the fixation unit is adapted to preventutilizing an implantable retention magnet to attach the loop structureto the user's body.

According to an embodiment, a medical device is disclosed. The medicaldevice includes an external unit and an implantable unit. The externalunit includes an electronic unit operationally coupled to a transmittercoil that is configured transmit power and/or data signal over awireless transcutaneous link, a coil unit comprising a loop structurewith the transmitter coil being wound around and along at least a partof length of the loop structure, and a fixation unit configured toattach the loop structure to a user's body i) proximal to an implantablereceiver coil that is configured to be implanted within a body part, andii) around a body part of a user such that a part of the body part ispositioned in a hollow section of the loop structure. The implantableunit includes the implantable receiver coil configured to receive thepower and/or data signal over the wireless transcutaneous link, aprocessing unit configured to i) process the received data signal tocontrol functionalities of at least one of the components of theimplantable unit, and/or ii) utilize the received power for operation ofat least one of the components of the implantable unit. The wirelesstranscutaneous link includes a coupling between the transmitter coil andthe receiver coil, and when the loop structure is attached using thefixation unit, at least a substantial number of magnetic field linesgenerated in response to excitation of the transmitter coil encircle thepart of the body part received in the hollow section of the loopstructure.

In one embodiment, the above disclosed embodiments are also applicablefor telemetry whereby feedback is provided from an implantable unit toan external unit such as in a cochlear implant system. In this set up,the above disclosed embodiments may be modified such that theimplantable receiver coil acts as an implantable transmitter coil andthe transmitter coil of the external unit acts as an external receivercoil. These modifications are within the scope of this disclosure. Suchset up would provide the same advantage in terms of coupling coefficientas embodiments disclosed earlier in this section.

Thus, in this embodiment, a medical device is disclosed. The medicaldevice includes an implantable unit and external unit. The implantabletransmitter coil is configured to transmit feedback telemetry data overa wireless transcutaneous link, and a processing unit configured toinstruct the implantable transmitter coil to transmit the feedbacktelemetry data. The external unit includes a coil unit comprising a loopstructure with an external receiver coil being wound around and along atleast a part of length of the loop structure, the external receiver coilbeing adapted to receive the feedback telemetry data, a fixation unitconfigured to attach the loop structure to a user's body i) proximal toan implantable transmitter coil that is configured to be implantedwithin a body part, and ii) around a body part of a user such that apart of the body part is positioned in a hollow section of the loopstructure. The wireless transcutaneous link comprises a coupling betweenthe implantable transmitter coil and the external receiver coil, andwhen the loop structure is attached using the fixation unit, at least asubstantial number of magnetic field lines generated in response toexcitation of the implantable transmitter coil passes through theexternal receiver coil.

The feedback telemetry data may include measurements and other dataregarding the operation and status of the implantable unit. The feedbacktelemetry data may also include in vivo biological data that includes,but not limited to, biological species and/or metabolites, glucoselevel, blood pressure, blood gas measurements, neural activity includingsignals directly from brain such as in a brain-computer interface, bodytemperature, and bodily part electrical activity. The in vivo biologicaldata may be obtained using an implantable sensor that is configured tocollect the in vivo biological data and transmit the collectedbiological data to the implantable processing unit, which is configuredto encode the biological data and transmit the encoded data as afeedback telemetry data using the wireless transcutaneous linkcomprising the implantable transmitter coil and the external receivercoil, as disclosed in the preceding paragraph. The implantable sensormay include, but not limited to, biochemical sensors, mechanicalsensors, electrical sensors, and neural prosthetic sensors.

Throughout the specification, unless stated explicitly otherwise,different disclosed embodiments should be considered combinable.

BRIEF DESCRIPTION OF DRAWINGS

The aspects of the disclosure may be best understood from the followingdetailed description taken in conjunction with the accompanying figures.The figures are schematic and simplified for clarity, and they just showdetails to improve the understanding of the claims, while other detailsare left out. Throughout, the same reference numerals are used foridentical or corresponding parts. The individual features of each aspectmay each be combined with any or all features of the other aspects.These and other aspects, features and/or technical effect will beapparent from and elucidated with reference to the illustrationsdescribed hereinafter in which:

FIG. 1 illustrates a medical device comprising a conventional wirelesstranscutaneous link;

FIG. 2 illustrates an implantable medical device comprising a wirelesstranscutaneous link according to an embodiment of the disclosure;

FIG. 3 illustrates an implantable medical device comprising a wirelesstranscutaneous link according to an embodiment of the disclosure;

FIG. 4A illustrates a closed loop structure in a closed mode accordingto an embodiment of the disclosure;

FIG. 4B illustrates a closed loop structure in an open mode according toan embodiment of the disclosure;

FIG. 4C illustrates a closed loop structure comprising a plurality ofparts (in a closed mode) according to an embodiment of the disclosure;

FIG. 4D illustrates a closed loop structure comprising a plurality ofparts (in an open mode) according to an embodiment of the disclosure;

FIG. 4E illustrates a closed loop structure in a closed mode accordingto an embodiment of the disclosure;

FIG. 5A illustrates an open loop structure according to an embodiment ofthe disclosure;

FIG. 5B illustrates an open loop structure according to an embodiment ofthe disclosure;

FIG. 5C illustrates an open loop structure according to an embodiment ofthe disclosure;

FIG. 5D illustrates an open loop structure comprising a plurality ofparts according to an embodiment of the disclosure;

FIG. 6A illustrates an open loop structure attached to a body partaccording to an embodiment of the disclosure;

FIG. 6B illustrates an open loop structure attached to a body partaccording to an embodiment of the disclosure;

FIG. 7 illustrates arrangement of the transmitter coil and the loopstructure with respect to the receiver coil according to an embodimentof the structure;

FIG. 8 illustrates a magnetic core positioned within the implantablereceiver coil according to an embodiment of the disclosure; and

FIG. 9 illustrates an implantable medical device comprising a wirelesstranscutaneous link according to an embodiment of the disclosure.

DETAILED DESCRIPTION

The detailed description set forth below in connection with the appendeddrawings is intended as a description of non-limiting exampleembodiments of the method and system according to the presentdisclosure. Throughout the drawings, same or at least functionallycomparable components are represented by same numerals. Throughout thetext, different features are illustrated using the same figure. Althoughsuch separate features are combinable, such illustration of differentfeatures in same figure should not be construed in a way that thesefeatures are disclosed only in combination. By way of example, FIG. 8discloses i) a magnetic core and ii) transmitter coil that is non-planarand non-coaxial with the receiver coil; these two features can beimplemented separately and also in combination.

FIG. 1 illustrates a medical device 100 comprising a conventionalwireless transcutaneous link. The device includes a primary (external)unit, external to the body, comprising a power source 102, an electronicunit 104 such as a power controller, and primary coil 108 through whichan alternating current is passed, creating a time-varying magnetic fieldlines 114,116. A secondary (implantable) unit, implantable under theskin and separable from the primary unit by thickness of the skin 112,contains a secondary coil 110. When the secondary coil 110 is placed inproximity to the time-varying magnetic field lines created by theprimary coil, the varying flux induces an alternating current in thesecondary coil, and thus power may be transferred inductively from theprimary unit to the secondary unit. The transferred power may beutilized by an implantable processing unit 106 and load 108. In this setup, the coupling coefficient is very low because most of the magneticfield lines 116 that the transmitter coil generates is not picked up bythe receiver coil and only a fraction of the magnetic field lines 114pass through the secondary coil 110, thus leading to poor energytransfer efficiency. Also, the primary coil 108 is arranged in adetachable manner at a position opposite to the implanted receiver coilsuch using retention magnets. The external unit typically includes atleast one retention magnet that cooperates with an implanted retentionmagnet in order to keep the external unit at the correct position overthe receiver coil such that the transmitter coil is axially aligned tothe receiver coil, i.e. coil axis of the two coils are aligned to eachother. However, in view of poor coupling coefficient, the primary unitusually includes a relatively huge battery compartment or multiplebatteries so that the implantable medical device is useable for a usageperiod that doesn't cause annoyance for the user. This results inincrease in size of the primary unit and even stronger retention magnetsand a heavier primary unit. This problem is further amplified becausethe two coils are located on either side of the skin, any change in coilseparation, for example by way of increase in thickness of skin tissue112, may result in rapid drop in the coupling coefficient between thetwo coils.

FIG. 2 illustrates an implantable medical device 200 comprising awireless transcutaneous link according to an embodiment of thedisclosure. The medical device 200 includes an external unit and animplantable unit. The external unit includes an electronic unit 204operationally coupled to a transmitter coil 220 that is configuredtransmit power and/or data signal over a wireless transcutaneous link, acoil unit comprising a loop structure 210 with the transmitter coil 220being wound around and along at least a part of length L of the loopstructure 210, and a fixation unit 214 configured to attach the loopstructure to a user's body (FIG. 3, 306) i) proximal to an implantablereceiver coil 212 that is configured to be implanted within a body part(FIG. 3, 310), and ii) around the body part (FIG. 3, 310) of a user suchthat a part (FIG. 3, 302) of the body part is positioned in a hollowsection 218 of the loop structure. The implantable unit includes theimplantable receiver coil 212 configured to receive the power and/ordata signal over the wireless transcutaneous link, a processing unit 206configured to i) process the received data signal to controlfunctionalities of at least one of the components of the implantableunit, and/or ii) utilize the received power for operation of at leastone of the components of the implantable unit. The wirelesstranscutaneous link includes a coupling between the transmitter coil 220and the receiver coil 212, and when the loop structure 210 is attachedusing the fixation unit 214, at least a substantial number of magneticfield lines 216 generated in response to excitation of the transmittercoil 220 passes through the implantable receiver coil 212.

The medical device may further include a power source 202 that providespower to the electronic unit 204, which among other functionalities alsoprovide power controlling functionality. The electronic unit 204 isconfigured to provide the transmitter coil with an alternating current,using the power source 202. The alternating current through thetransmitter coil 220 produces a time-varying magnetic field lines 216, asubstantial number of which are adapted to pass through the implantablereceiver coil 212 when the loop structure 210 is attached to the bodyusing the fixation unit 214. The time-varying magnetic field linespassing through the receiver coil 212 induces an alternating current inthe receiver coil 212, and thus data and/or power may be transferredinductively from the external unit to the implantable unit. Because asubstantial number of field lines are adapted to pass through theimplantable receiver coil, the coupling coefficient is very high andindependent of the separation between the transmitter coil and receivercoil and/or thickness of the body tissue. 208 represents a load such asan implantable electrode array or an implantable vibrator or animplantable vibratory unit.

In an embodiment, the above disclosed embodiment and followingembodiment are also applicable for telemetry whereby feedback isprovided from the implantable unit to the external unit such as in acochlear implant system. In this set up, the above disclosed embodiment(and following embodiments) may be modified such that the implantablereceiver coil 212 acts as an implantable transmitter coil and thetransmitter coil 220 of the external unit acts as an external receivercoil. In such telemetry embodiments, the implantable processing unit 206is configured to provide the implantable receiver coil 212 (acting as atransmitter coil) with an alternating current and a time varyingmagnetic flux 224 is created. When the loop structure 210 comprisingwound transmitter coil (acting as an external receiver coil) ispositioned on the body using the fixation unit 214, a substantial amountof the time varying magnetic flux 224 passes through the transmittercoil (acting as an external receiver coil) thus inducing alternatingcurrent in the transmitter coil (acting as an external receiver coil).Because a substantial amount of magnetic flux is adapted to pass throughthe transmitter coil (acting as an external receiver coil), the couplingcoefficient is very high and independent of the separation between thetransmitter coil and receiver coil and/or thickness of the body tissueand/or skin.

FIG. 3 illustrates an implantable medical device comprising a wirelesstranscutaneous link according to an embodiment of the disclosure. Thefixation unit 214 is configured to attach the loop structure 210 to auser's body (ear) 306. The loop structure 210 is positioned proximal toan implantable receiver coil 212 that is configured to be implantedwithin a body part (ear lobe) 310, and ii) around the body part 310 of auser such that a part 302 of the body part is positioned in a hollowsection 218 of the loop structure 210. Although it is not necessary forexample in an open loop structure, but this embodiment illustrates thatthe fixation unit 214 is configured penetrate through the body part 310at least at one point 304 of the body part. In this embodiment, theanterior side is the front side 312 and the posterior side is the backside 314.

FIG. 9 illustrates an implantable medical device comprising a wirelesstranscutaneous link according to an embodiment of the disclosure. Theloop structure 210 is positioned proximal to an implantable receivercoil 212 that is configured to be implanted within a body part(periumbilical region) 904. The fixation unit 214 is configured toattach the loop structure 210 to a user's body (abdomen) 902 such thatthe loop structure 210 is positioned around a the body part (i.e. skinin the periumbilical region 904) and the loop structure extends, with(such as in the closed loop structure) or without (such as in open loopstructure) piercing through the skin, between a posterior side 914 andan anterior side 912 of the skin and with a part of the skin 906 beingpositioned in the hollow section 218 of the loop structure 210. Althoughit is not necessary for example in an open loop structure, but thisembodiment illustrates that the fixation unit 214 is configuredpenetrate through the body part at least at one point 908 of the bodypart. The implantable receiver coil is preferably configured to beimplanted around the umbilicus 910 of the user.

In different embodiments, the body part may include other implantationsites on the user's body such as tragus, body tissue over mastoidregion, superciliary arch, and any other suitable location.

FIG. 4 illustrates a loop structure 210 that is defined by a geometricalshape that includes a closed curve, defining a closed loop structure(FIG. 4A, FIG. 4C, FIG. 4E), wherein a point S moving along the closedcurve forms a path (counter clockwise direction starting from S) from astarting point S to a final point E that coincides with the startingpoint when the closed curve is in a closed mode (FIG. 4A, FIG. 4C). Inone embodiment, the closed curve may include a single part loopstructure (FIG. 4A, FIG. 4B, FIG. 4E) comprising an openable section(214, FIGS. 4A through 4E) that includes a primary end (422, FIG. 4B)and a secondary end (424, FIG. 4B). The openable section is attached torest section of the loop structure at the primary end and adapted toopen the section at the secondary end. The open mode is defined when theopenable section is open (FIG. 4B) to allow access to the hollow sectionand positioning of the part (302, FIG. 3) of the body part (310, FIG. 3)within the hollow section (FIG. 3, 218). The closed mode is defined whenthe openable section (214, FIG. 4B) is engaged with rest of the sectionat the secondary end (424, FIG. 4B) to form the closed curve. In oneembodiment FIG. 4A and FIG. 4B, the fixation unit 214 comprises a pin408, one end 412 of the pin is attached in swivel arrangement with theloop structure at a point 410 and another end of the pin 424 is adaptedto be received in a hole 406 of the loop structure. The swivel action ofthe pin changes the mode of the loop structure from the closed mode(FIG. 4A) to the open mode (FIG. 4B) and vice versa. The pin 408 isadapted to penetrate through a body part at least at one point. Inanother embodiment of FIG. 4E, the fixation unit includes an openablesection (clamp, 214) that includes a primary end 422 and a secondary end424. The clamp 214 includes a threaded shaft 408 that is adapted to beinteract with the thread 426 provided at the loop structure in order toscrew the clamp in and out of the hole 406 using the handle 414 of theclamp. The shaft is adapted to penetrate through the body part at leastat one point. FIG. 4E illustrates a closed mode but it is understandablethat the clamp is adapted to be unscrewed and opened such that the loopstructure is brought into an open mode to allow positioning of the part(FIG. 3, 302) of the body part (FIG. 3, 310) within the hollow section(FIG. 3, 218) of the loop structure 210.

Alternatively, the closed curve may include multi-parts loop structure(FIG. 4C and FIG. 4D) wherein the multi-parts includes a plurality ofdetachable parts, such as a first sub-part 402 and a second sub-part404, that are configured to attach with one another to form a closedloop structure (FIG. 4C). In this embodiment, a snap-lock mechanism isdisclosed in in order to attach the first sub part 402 with the secondsub part 404. The snap lock mechanism includes one or moreprotrusion-hole pair that are adapted to detachably connect to eachother. For example, the snap lock mechanism includes a protrusion (416,416′) at one of the sub-part (402, 404) that is adapted to be receivedin a hole (418, 418′) in another of the sub part (404, 402). Althoughthe illustration shows that each sub part includes a protrusion and ahole but it is equally possible that both the protrusions are providedat the same sub part and corresponding interacting holes provided atanother sub part. In one embodiment, each protrusion is adapted topenetrate through the body at distinct point. For example, if one of thesub parts include both protrusions, then each protrusion is adapted topenetrate through the body at distinct spatially separated points. Inanother embodiment, only one protrusion is penetrate through the body atleast at one point. The closed mode is defined when the plurality ofdetachable parts is attached to one another (FIG. 4C). Accordingly, inFIG. 4D, an open mode is defined when the plurality of detachable partsis not attached to one another and in the open mode, the loop structureis adapted to allow positioning of the part (FIG. 3, 302) of the bodypart (fig.3, 310) within the hollow section (FIG. 3, 218) of the loopstructure 210. The skilled person would appreciate that other mechanismsother than snap mechanism for the fixation unit may also be employed.

The reference numeral 420 represents a loop axis that runs along lengthof the closed loop structure.

FIG. 5 discloses a loop structure 210 is defined by a geometrical shapethat includes an open curve, defining an open loop structure, wherein apoint S moving along the open curve forms a path (anti-clockwisedirection starting from point S) from a starting point S to a finalpoint E that is proximal to but separated from the starting point by adistance D. The distance is typically a function of a thickness of thebody tissue and/or skin to which the loop structure is attached, i.e.the distance is configured such that the loop structure is attachable tothe user's body. In one embodiment (FIG. 5A), the fixation unit includesat least one spring 502 arranged between the inner surface of oppositearms of the loop structure such that the at least one spring is adaptedto provide a pulling force between the two arms. The distance D issmaller than the thickness of the body tissue and the spring providessufficient pulling force for providing a compressive retention force(FIG. 6B) between the first end (FIG. 6B, 602) and second end (FIG. 6B,604) of the loop structure in order to attach the loop structure to thebody. The user may apply a force countering and in excess of the pullingforce in order to detach the loop structure from the body or to allowpositioning of the part (FIG. 6, 302) of the body part (FIG. 6, 310)within the hollow section (FIG. 6, 218) of the loop structure 210. Abalance between comfort and the retention force may be achieved based onchoice of a spring with an appropriate spring constant. In anotherembodiment (FIG. 5B), the fixation unit includes a clamp 508 comprisinga threaded shaft. The threaded shaft—loop structure thread pair 512 areadapted to cooperate with each other such that the distance D betweenthe one end (FIG. 6B, 602 or 604) of the loop structure and an end face510, opposite to the one end of the loop structure, is reduced byscrewing the clamp towards the one end of the loop structure. Suchreduction in the distance D allows for providing a compressive retentionforce between the one end of the loop structure and the end face 510 inorder to attach the loop structure to the body. In this embodiment, thedistance D is more than the thickness of the body tissue. A sufficientscrewing of the clamp away from the one end of the loop structure may beused to detach the loop structure from the body part or to allowpositioning of the part (FIG. 6, 302) of the body part (FIG. 6, 310)within the hollow section (FIG. 6, 218) of the loop structure 210. Theadvantage of the fixation unit comprising clamp is that the user mayfind a balance between comfort and compressive retention force. In yetanother embodiment (FIG. 5C), the fixation unit relies on thebendability of the loop structure 210. The distance D is smaller thanthe thickness of the body tissue and the arms (526, 528) of the loopstructure are adapted to be pulled apart in order to receive the part ofthe body part in the hollow section. The bendability of the loopstructure at points 530 and 532 pulls the arms 526 and 528 towards eachother such that a compressive retention force (FIG. 6B) between thefirst end (FIG. 6B, 602) and second end (FIG. 6B, 604) of the loopstructure is applied in order to attach the loop structure to the body.The user may apply a force countering and in excess of the bendabilitybased pulling force in order to detach the loop structure from the bodyto allow positioning of the part (FIG. 6, 302) of the body part (FIG. 6,310) within the hollow section (FIG. 6, 218) of the loop structure 210.A balance between comfort and the retention force may be achieved basedon choice of a bending properties of the loop structure. This embodimentis particularly simple to manufacture.

Alternatively, the open curve may include multi-parts loop structure(FIG. 5D) wherein the multi-parts includes a plurality of detachableparts, such as a first sub-part 516 and a second sub-part 518, that areconfigured to attach with one another to form the open loop structure(FIG. 5D). In one embodiment (FIG. 5D), a snap-lock mechanism isdisclosed in order to attach the first sub part 516 with the second subpart 518, where one part 516 includes a hole 522 that is adapted toreceive a protrusion 524 provided at the second part 518. The fixationunit includes a clamp mechanism that is similar in operation as theclamp disclosed in FIG. 5B. In another embodiment (not shown), amagnetic locking mechanism (instead of snap-lock mechanism 522-524 inFIG. 5D) is disclosed in order to attach the first sub part (516, FIG.5D) with the second sub part (518, FIG. 5D). The fixation unit includesa pair of magnets (instead of clamp mechanism of FIG. 5D) that provide apulling force to reduce the distance (D, FIG. 5D), which is greater thanthickness of the body tissue. The pulling force provides a compressiveretention force in order to attach the loop structure to the body part.The loop can be detached simply by pulling and applying sufficient forceovercoming the pulling magnetic force provided by the magnet pair. Thechoice of magnets in the magnet pair may provide a balance betweenreliability in retention and comfort level.

The numeral 506 illustrates an extrapolated loop axis by an axis thatruns along the entire length of the loop structure 210 and an imaginaryline 504 joining the distance D separating the first end (FIG. 6B, 602)of the loop structure 210 and second end (FIG. 6B, 604) of the loopstructure 210.

In different embodiments, the loop structure 210 may include shape thatis selected from a circular (FIGS. 4A, 4B, 5D), elliptical (FIG. 5A),rectangular (FIGS. 4C, 5B), square (FIGS. 4C, 5B), polygonal shape(FIGS. 4C, 5B), curved shape (FIGS. 4A, 4B, 5C) or a combination thereof(FIG. 4E).

In view of any of the FIGS. 3 through 6, it is evident that the fixationunit 214 is configured to attach the loop structure 210 proximal to theimplantable receiver coil 212 (FIGS. 3, 6) such that a loop axis (FIG.4, 420) or an extrapolated loop axis (FIG. 5, 506) of the loop structurepasses through the implantable receiver coil (FIG. 3, FIG. 6, 212).

FIG. 6A illustrates an open loop structure attached to a body partaccording to an embodiment of the disclosure. The open loop structurecomprises a transmitter coil 220 wound around the loop structure. Thefixation unit includes a spring 502 providing a pulling compressiveretention force (similar to embodiment disclosed in FIG. 5A). The hollowsection 218 is adapted to position a part 302 of the body part 310. Whenthe transmitter coil 220 is excited, a substantial part of the generatedmagnetic field lines (represented by anticlockwise arrows) pass throughthe implantable receiver coil 212. The implementation in FIG. 6A issimilar to the one disclosed earlier in FIG. 3 except FIG. 6A utilizesan open loop structure as opposed to the closed loop structure of FIG.3. In this embodiment, there might be some leakage of the magnetic fieldlines because of sandwiched skin and body tissue between the two ends(FIG. 6B, 602, 604) of the loop structure 210 instead of a continuousloop structure as disclosed in FIG. 3 that illustrates positioning ofthe closed loop structure. Nonetheless, the skilled person wouldappreciate that despite some leakage, a substantial amount of magneticfield lines generated in response to excitation of the transmitter coilwould still follow the path of the imaginary line because of the shortdistance between first end and the second end of the loop structure, inparticular, when an implantable magnetic core (FIG. 8, 814) isconfigured to be positioned within the area enclosed by the perimeter ofthe implantable receiver coil.

FIG. 6B illustrates an open loop structure attached to a body partaccording to an embodiment of the disclosure. This figure provides acloser illustration of the retention mechanism of the disclosure of FIG.6A. The loop structure comprises an openable open loop structurecomprising a slit (generally defined by the distance D, see FIG. 5)having a first slit end 602 configured to abut a first skin surface 606of the user and a second slit end 604, opposite to the first slit end602, configured to abut a second skin surface 608 of the user, the firstskin surface 606 and the second skin surface 608 being separated by abody tissue 618.

In an embodiment, the first slit end 602 is adapted to face a firstplanar side 610 of the implantable receiver coil 212; and a second slitend 604 that is adapted to face a second planar side 612, opposite tothe first planar side 610, of the implantable receiver coil 212.

The fixation unit (spring 502) arranged between the inner surface ofopposite arms of the loop structure may be adapted to provide a pullingforce between the two arms such that a compressive retention force (asrepresented by compressed skin and body tissue) between the first end602 and second end 604 is provided to attach the loop structure 210 tothe body.

In view of any one of the FIGS. 3 and 6A, it is evident that thetransmitter coil 220 and the implantable receiver coil 212 are arrangedrelative to each other such that the coupling coefficient between thetransmitter coil 220 and the implantable receiver coil 212 isindependent of orientation of the transmitter coil 220 with respect tothe implantable receiver coil 212. The coupling coefficient thus dependsupon the arrangement of the loop structure 210 with respect to theimplantable receiver coil 212. This arrangement may include interlockedhopf configuration between the loop structure 210 and implantablereceiver coil 212.

In another embodiment, planar area (along plane 610 or 612) of theimplantable receiver coil 212 is at least same as the cross sectionalarea (as seen from X-X′ in the direction of 614 and/or 616) of the loopstructure 210 at an interface (604 or 602) of the loop structure.

FIG. 7 illustrates arrangement of the transmitter coil and the loopstructure with respect to the receiver coil according to an embodimentof the structure. In an embodiment, the lengthwise distance L1 and/or L2between the transmitter coil 220 and receiver coil 212 is more thandiameter of the receiver coil 702. Additionally, or alternatively, thelengthwise distance L1 and/or L2 between the transmitter coil 220 andreceiver coil 212 is more than diameter 704 of the transmitter coil 220.L represents the at least part of length of the loop structure aroundwhich the transmitter coil is wound.

In another embodiment, diametric dimensions 702 of the implantablereceiver coil 212 is at least same as width of the loop structure. Thewidth refers to cross-sectional thickness of the loop structure as seenfrom X-X′ in the direction of 710 and/or 712. In another embodiment,planar area (along plane 802, FIG. 8) of the implantable receiver coil212 is at least same as the cross sectional area (as seen from X-X′ inthe direction of 710 and/or 712) of the loop structure 210 at aninterface of the loop structure. The cross sectional area of the loopstructure 210 at the interface of the loop structure may include i)cross sectional area at the first end (FIG. 6B, 602) and/or the secondend (FIG. 6B, 604) of the loop structure, or ii) cross sectional area ofthe section (408 or FIG. 4C, 416) of the loop structure that penetratesthrough the body part at least at one point of the body part.

FIG. 8 illustrates a magnetic core positioned within the implantablereceiver coil according to an embodiment of the disclosure. In anembodiment, at least one turn of the transmitter coil is non-parallel tothe implantable receiver coil, as illustrated by planes 804 and 806being non-parallel to 802. Additionally, or alternatively, at least oneturn of the transmitter coil is non-coaxial with the receiver coil, asillustrated by axis 810 and 812 being non-coaxial with 808. In anembodiment, the implantable receiver coil 212 is in a first plane 802and the loop structure is along a second plane (parallel to the surfaceof paper). The first plane 802 and the second plane being at leastsubstantially perpendicular to each other.

In another embodiment, the implantable unit comprises an implantablemagnetic core 814 that is configured to be positioned within an areaenclosed by a perimeter of the implantable receiver coil 212. Themagnetic core is adapted to direct the magnetic field lines to passthrough the implantable receiver coil, thus further improving thecoupling coefficient between the transmitter coil and receiver coil.

In view of any one of the FIGS. 2, 3, 6 through 8, it is evident thatthe fixation unit 214 is configured to attach the loop structure 210around the body part (FIGS. 3, 6A, 310) such that the loop structure 210and the implantable receiver coil 212 are arranged in an interlockedhopf link configuration.

In view of any one of the FIGS. 2, 3, 6 through 8, it is evident thatthe fixation unit 214 is configured to attach the loop structure 210around the body part (FIGS. 3, 6 310) such that i) the loop structure210 and the implantable receiver coil 212 are arranged in an interlockedfirst hopf link configuration, and ii) the loop structure 210 and thetransmitter coil 220 are arranged in an interlocked second hopf linkconfiguration.

In an embodiment, the fixation unit 214 is selected from a groupconsisting of a non-magnetic fixation unit (FIGS. 4A through 4E andFIGS. 5A through 5D) and a fixation mechanism that is adapted to attachthe loop structure to a user's body independent of any cooperation(interaction) with the implantable unit (FIGS. 4 and 5).

In an embodiment, the fixation unit is selected from a group consistingof a clamp mechanism (FIGS. 4E, 5B, 5D), spring mechanism (FIG. 5A),piercing pin mechanism (FIGS. 4A, 4B, 4C, 4D, 4E), snap-couplingmechanism between the first sub-structure and second sub-structure(FIGS. 4C, 4D, 5D), a magnetic coupling mechanism between the firstsub-structure and second sub-structure, and a combination thereof (FIG.5D).

In an embodiment, the processing unit is configured to process thereceived data signal and generate an output. The output is configured togenerate perceivable stimulation for the user. For example, suchperceivable stimulation includes perception of sound in case ofimplantable hearing aids. The medical device thus may be selected from agroup consisting of one or more of

i) an implantable hearing aid comprising a cochlear implant comprisingan implantable electrode array configured to be positioned within acochlea of the user, the electrode array being configured to deliverelectrical charges in accordance with the output. A typical,non-limiting, description of such cochlear implant is available inpending European patent application EP3045204 (A cochlear implant and anoperating method thereof), in particular in FIG. 1B of the referredapplication where numeral 160 (signal processor) of the referredapplication illustrates the disclosed electronic unit (FIG. 2, 204),numeral 155 (pulse generator) of the referred application illustrates atleast a part of the disclosed implantable processing unit (FIG. 2, 206)and numeral 9 (electrode array) of the referred application illustratesthe disclosed electrode array (FIG. 2, 208). The referred application isincorporated herein by reference.

ii) an implantable hearing aid comprising an auditory transmodiolarimplant comprising an implantable electrode array configured to bepositioned within a modiolus of the user, the electrode array beingconfigured to deliver electrical charges in accordance with the output.A typical, non-limiting, description of the disclosed electronic unit(FIG. 2, 204) and at least a part of the disclosed implantableprocessing unit (FIG. 2, 206) that may be used in such auditorytransmodiolar implant is available in FIG. 1B of pending European patentapplication EP3045204 (A cochlear implant and an operating methodthereof) by numeral 160 (signal processor) and numeral 155 (pulsegenerator) respectively of the referred application. The implantableelectrode array (FIG. 2, 208) that is specifically adapted for auditorytransmodiolar implant is disclosed in FIG. 2 of the pending Europeanpatent application EP3017843 (Transmodiolar electrode array and amanufacturing method). The referred applications are incorporated hereinby reference.

iii) an implantable hearing aid comprising an auditory brainstem implantcomprising an implantable electrode array (typically provided as a pad)configured to be implanted directly onto brainstem, the electrode arraybeing configured to deliver the electrical charges in accordance withthe output. A typical, non-limiting, description of such auditorybrainstem implant is provided in the granted patent U.S. Pat. No.8,874,238 (Conformal Electrode pad for a stimulating medical device) andin particular in FIG. 1B where numeral 126 (speech processing unit) ofthe referred patent illustrates the disclosed electronic unit (FIG. 2,204), numeral 134 (stimulator) of the referred patent illustrates atleast a part of the disclosed implantable processing unit (FIG. 2, 206),and numeral 140 (electrode pad) of the referred patent illustrates thedisclosed electrode array (FIG. 2, 208). The referred patent isincorporated herein by reference.

iv) an implantable hearing aid comprising a bone conduction hearing aidcomprising an implantable vibrator configured to be attached to skull ofthe user, the vibrator being configured to generate vibrations inaccordance with the output. A typical, non-limiting, description of suchimplantable hearing aid is provided in granted European patent EP1972179(Hearing aid system) illustrating an implantable vibrator unit (FIG. 1,106) that illustrate the disclosed vibrator (FIG. 2, 208). A typical,non-limiting, description of such implantable hearing aid is alsoprovided in granted U.S. Pat. No. 9,554,222 (Electromechanicaltransducer with mechanical advantage) where external speech processingunit (FIG. 2B, 100) illustrates the disclosed electronic unit (FIG. 2,204), bone conduction transducer (FIG. 2B, 200) illustrates thedisclosed implantable processing unit (FIG. 2, 206) and vibrator (FIG.2. 208). The referred patent is incorporated herein by reference.

v) an implantable hearing aid comprising a middle ear implant comprisinga vibratory unit configured to attach to one of the bones of the middleear and/or to one of the windows of the cochlea, the vibratory unitbeing configured to generate vibrations in accordance with the output. Atypical, non-limiting, description of such middle ear implant isprovided in withdrawn European patent application EP2129428 (Implantableauditory stimulation systems having a transducer and a transductionmedium) where the audio processor of the referred application in FIGS. 3and 4 represents the disclosed electronic unit (FIG. 2, 204),demodulation electronics of the referred application in FIGS. 3 and 4illustrates at least a part of the disclosed implantable processing unit(FIG. 2, 206), and FMT with transduction medium (FIG. 2) or plunger typetransducer (FIG. 3) of the referred application illustrates thevibratory unit (FIG. 2, 208). The referred application is incorporatedherein by reference.

vi) an artificial pacemaker comprising an electrode array configured todeliver electrical charges in accordance with the output. A typical,non-limiting, description of such artificial pacemaker is provided ingranted European patent EP2376193 (Shunt-current reduction techniquesfor an implantable therapy system) which illustrates an implantablecardiac device (FIG. 1, 16) that illustrates a part of the implantableprocessing device (FIG. 2, 206) and electrodes (FIG. 7A, 124)illustrating disclosed electrode array (FIG. 2, 208). The referredpatent is incorporated herein by reference.

It should be appreciated that reference throughout this specification to“one embodiment” or “an embodiment” or “an aspect” or features includedas “may” means that a particular feature, structure or characteristicdescribed in connection with the embodiment is included in at least oneembodiment of the disclosure. Furthermore, the particular features,structures or characteristics may be combined as suitable in one or moreembodiments of the disclosure. The previous description is provided toenable any person skilled in the art to practice the various aspectsdescribed herein. Various modifications to these aspects will be readilyapparent to those skilled in the art, and the generic principles definedherein may be applied to other aspects.

The claims are not intended to be limited to the aspects shown herein,but is to be accorded the full scope consistent with the language of theclaims, wherein reference to an element in the singular is not intendedto mean “one and only one” unless specifically so stated, but rather“one or more.” Unless specifically stated otherwise, the term “some”refers to one or more.

Accordingly, the scope should be judged in terms of the claims thatfollow.

1. A hearing aid device comprising an external unit configured to beworn proximate to a user's ear, the external unit comprising anelectronic unit operationally coupled to a transmitter coil that isconfigured transmit power and/or data signal over a wirelesstranscutaneous link, a coil unit comprising a loop structure with thetransmitter coil being wound around and along at least a part of lengthof the loop structure, a fixation unit configured to attach the loopstructure to the user's ear proximal to a loop-shaped implantablereceiver coil that is configured to be implanted within the ear oraround the ear of the user such that a part of the ear is positioned ina hollow section of the loop structure; and an implantable unitcomprising the implantable receiver coil configured to receive the powerand/or data signal over the wireless transcutaneous link, and aprocessing unit configured to i) process the received data signal tocontrol functionalities of at least one of the components of theimplantable unit, and/or ii) utilize the received power for operation ofat least one of the components of the implantable unit, wherein thewireless transcutaneous link comprises a coupling between thetransmitter coil and the receiver coil, and when the loop structure isattached using the fixation unit such that at least a substantial numberof magnetic field lines generated in response to excitation of thetransmitter coil passes through the opening in the loop-shapedimplantable receiver coil.
 2. The hearing aid device according to claim1, wherein the fixation unit is adapted to attach the loop structurewith respect to the implantable receiver coil in an arrangement suchthat one section of the implantable receiver coil is positioned withinthe hollow section of the loop structure whereas the other section ofthe implantable receiver coil is positioned outside the hollow sectionof the loop structure.
 3. The hearing aid device according to claim 1,wherein the fixation unit is configured to attach the loop structureproximal to the implantable receiver coil such that the loop structurepasses through the implantable receiver coil and the implantablereceiver coil winds around a segment of the loop structure.
 4. Thehearing aid device according to claim 1, wherein the fixation unit isconfigured to attach the loop structure around the ear such that theloop structure and the implantable receiver coil are arranged in aninterlocked hopf link configuration.
 5. The hearing aid device accordingto claim 1, wherein the loop structure comprises an openable closed loopstructure comprising a section that is configured to penetrate throughthe body part at least at one point of the body part.
 6. The hearing aiddevice according to claim 1, wherein the loop structure comprises anopenable open loop structure comprising a slit having a first slit endconfigured to abut a first skin surface of the user and a second slitend, opposite to the first slit end, configured to abut a second skinsurface of the user, the first skin surface and the second skin surfacebeing separated by a body tissue.
 7. The hearing aid device according toclaim 6, wherein the first slit end is adapted to face a first planarside of the implantable receiver coil; and a second slit end is adaptedto face a second planar side, opposite to the first planar side, of theimplantable receiver coil.
 8. The hearing aid device according to claim1, wherein a planar area of the implantable receiver coil is at leastthe same as a cross sectional area of the loop structure at an interfaceof the loop structure.
 9. The hearing aid device according to claim 1,wherein the implantable unit comprises an implantable magnetic core thatis configured to be positioned within an area enclosed by a perimeter ofthe implantable receiver coil.
 10. The hearing aid device according toclaim 1, wherein the at least a substantial number of magnetic fieldlines generated in response to excitation of the transmitter coil aregenerated within the loop structure.
 11. The hearing aid deviceaccording to claim 1, wherein at least one turn of the transmitter coilis non-parallel to the implantable receiver coil.
 12. The hearing aiddevice according to claim 1, wherein the loop structure comprises afirst sub-structure and a second sub-structure, the first sub-structureand the second sub-structure being configured to operationally connectwith each other to form an openable closed loop structure or openableopen loop structure.
 13. The hearing aid device according to claim 1,wherein the fixation unit is selected from a group consisting of anon-magnetic fixation unit and a fixation mechanism that is adapted toattach the loop structure to a user's ear independent of any cooperationwith the implantable unit.
 14. The hearing aid device according to claim1, wherein the fixation unit is selected from a group consisting of aclamp mechanism, spring mechanism, piercing pin mechanism, snap-couplingmechanism between the first sub-structure and second sub-structure, amagnetic coupling mechanism between a first sub-structure and secondsub-structure that are configured to operationally connect with each,and a combination thereof.
 15. The hearing aid device according to claim1, wherein the processing unit is configured to process the receiveddata signal and generate an output, and the electrode array isconfigured to deliver electrical charges in accordance with the output.16. The hearing aid device according to claim 2, wherein the fixationunit is configured to attach the loop structure proximal to theimplantable receiver coil such that a loop axis or an extrapolated loopaxis of the loop structure passes through the implantable receiver coil.17. The hearing aid device according to claim 2, wherein the fixationunit is configured to attach the loop structure around the body partsuch that the loop structure and the implantable receiver coil arearranged in an interlocked hopf link configuration.
 18. The hearing aiddevice according to claim 3, wherein the fixation unit is configured toattach the loop structure around the body part such that the loopstructure and the implantable receiver coil are arranged in aninterlocked hopf link configuration.
 19. The hearing aid deviceaccording to claim 2, wherein the loop structure comprises an openableclosed loop structure comprising a section that is configured topenetrate through the body part at least at one point of the body part.20. The hearing aid device according to claim 3, wherein the loopstructure comprises an openable closed loop structure comprising asection that is configured to penetrate through the body part at leastat one point of the body part.